Abrasive throwing machine



1 1940- J. E. GUENDLING ABRASIVE THROW-1N6 MACHINE 4 Sheets-Sheet 1Filed March 22, 1938 INVENTOR Joim E. fiaenalig ATTORNEY Dec. 10, 1940.J, U N 2,224,153

ABRASIVE THROWING MACHINE Filed Mal-ch22, 1958 4 Sheets-Sheet 2 INVENTORE John If fiumali g 1 BY m 1 4'5 ATTORNEY Dec. 10, 1940. GUENDUNG2,224,153

ABRASIVE THROWING MACHINE Filed March 22, 1938 4 Shee1'Is-Sheet 3 ,4;ATTORNEY Dec. 10, 1940. J. E. GUENDLING ABRASIVE THROWING' MACHINEFiloddlaroh 22, I938 4 Sheets-Sheet 4 MA ww n T m Mm K m Ms PatentedDec. 10, 1940,;

ABRASIVE THROWING MACHINE John E. Guendling, South Bend, Ind., assignorto The American Foundry Equipment Company, Mishawaka, Ind., acorporation of Delaware Application March 22, 1938, Serial No. 197,339

11 Claims.

This invention relates to abrasive throwing machines and moreparticularly to a throwing wheel of the centrifugal type having improvedmeans for controlling the direction of flight of the thrown abrasive.

According to the invention, the machine comprises a rotor having aplurality of throwing blades extending from the periphery of the rotorto points inwardly short of the axis of rotation of the wheel to providea central space, the blades being suitably mounted for rotation aboutthe axis of the rotor. Abrasive is fed to the rotating blades through acontrol member extending into the space provided centrally of therotor'and having an abrasive discharge outlet in the tubular side wallthereof. An impel1er comprising one or more vanes which extend into thetubular control member and is mounted to rotate with the blades to throwabrasive through the discharge outlet in the control member and into thepath of rotation of the blades. The control member and impeller are soshaped and positioned relative to each other and to the other portionsof the rotor as to minimize the entry of uncontrolled abrasive materialinto the path of rotation of the blades, thus reducing the possibilityof clogging or undue wear.

In an illustrative embodiment of the invention the control membercomprises a generally tubular side wall portion which is open at one endto permit the entry of abrasive and closed at the other end as by an endwall. A stud extends from the end wall into the tubular side wallportion but is spaced therefrom to permit the impeller to run in thespace therebetween. The stud provides a means by which the controlmember may be adjustably supported. The stud may be tubular in form andmay be connected to the discharge end of the feed pipeso that theabrasive may pass into the tubular stud and escape therefrom through oneor more openings provided therein. The impeller comprises a memberhaving a plurality of spaced, generally radial vanes positioned betweenthe stud and the tubular side wall portion of the control member and aportion which is seouredto the feed side of the rotor to securely andrigidly support the impeller with respect to the rotor blades.

An object of the invention is the provision of an abrasive throwingmachine provided with a Another object of the invention is to provide.

an abrasive throwing wheel of the type having rotating blades and arelatively fixed control member for controlling the supply of abrasivematerial to the blades wherein spillage of the abrasive is minimized andwherein any abrasive which is not deposited on the blades is removed 5from the interior of the wheel.

. Still another object of the invention is the provision of an abrasivethrowing wheel of the type having rotating vblades and an impellerrotatable therewith wherein the impeller is firmly and securely mountedin a novel manner. for rotation with the blades. 7

Various other features and advantages of the invention will be apparentfrom the following particular description and from an inspection of theaccompanying drawings.

Although the novel features which are believed to be characteristic ofthis invention will be particularly pointed out in the claims appendedhereto, the invention itself, as to its objects and advantages, and themanner in which it may be carried out, may be better understood byreferring to the following description taken in connection with theaccompanying drawings forming a part thereof, in which Fig. 1 is afragmentary, side elevational view of an abrasive throwing rotorconstructed in accordance with the invention, having the improved devicefor controlling the direction of discharge of the thrown abrasiveincorporated therewith;

Fig. 2 is a transverse cross-sectional view taken along line 2-2 of Fig.1;

Fig. 3 is a longitudinal cross-sectional view through the machine takenalong line 3-3 of Fig. 2;

Fig. 4 is a fragmentary cross-sectional view taken along line 4-4 ofFig. 2 and through the improved control device associated with theabrasive throwing rotor;

Fig. 5 is an exploded perspective view of certain operativeelements'forming the control device, certain parts being broken away toillustrate more clearly certain features of the construction;

Fig. 6 is a fragmentary cross-sectional view of the central portion ofthe rotor and showing an alternative form of control member;

Fig. 7 is a. fragmentary cross-sectional view the central portion of thewheel and showing an alternative form of impeller;- 1

Fig, 10 is a fragmentary cross-sectional view taken along line Ill-40 ofFig. 9;

Fig. 11 is a fragmentary side elevational view of the discharge end ofthe feed pipe and the tubular control member, showing alternative meanswhich may be employed for securing these parts together, certain partsbeing shown in section to more clearly illustrate the construction; and!Fig. 12 is a cross-sectional view taken along line l2--l2 of Fi 11.

In the following description and in the claims, various details will beidentified by specific names for convenience, but they are intended tobe as generic in their application as the art will permit. Likereference characters denote like parts in the several figures of thedrawings.

The improved'device for obtaining more accu-.

rate directional control of the thrown particles may be associated withany suitable rotor adapted to be driven at high speed and provided withsuitably arranged abrasive throwing blades. Referring particularly toFigs. 1, 2 and 3, there is shown for purposes of illustration one formof rotor which may be used, comprising a rotor disc or side wall memberI which is operatively secured to a high speed drive shaft 6. To givestrength and sturdiness to the construction a hub member I is suitablysplined or otherwise secured to the drive shaft 8 and is secured bybolts: B or other means to the rotor disc I.

V One or more abrasive throwing blades b are suitably mounted on therotor disc i and extend inwardly short of the axis of rotation of therotor whereby their inner ends define a central space a. To provideadditional support for the blades b, and to provide a support to whichthe rotating impeller, hereafter described, may be secured, a side wallmember or disc 2 having a central opening therein may be provided. Thedisc member 2 may be held in substantially parallel, fixed, spacedrelationship with the rotor disc i by any suitable means, For purpose ofillustration, there is shown a series of spaced studs 3 having shoulders4 thereon, which abut the inside face of the adjacent side wall plates iand 2 and heads 5, which are burnished or otherwise suitably secured tothe side wall plates 8 and 2.

The blades b may be held in fixed, suspended position between the sidewall plates by providing paired radially extending grooves in the sidewall plates l and 2 within which the side edges of the blades seat.There is shown for purposes of illustration a throwing wheel having aseries of eight, spaced, radially arranged blades b, each comprising athrowing surface or bottom wall portion 70 and flange or side wallportions H extending in the direction of rotation of the wheel toconfinethe moving abradant or comminuted material on the working faceill of the blade b and between the side flange ii thereof. The blades bmay be secured in place by set screws 90 extending through one of theside plates and entering notches or depressions Si in the blades b.

To insure smooth pick-up of the abradant material at the inner end ofthe blade b, the inner end of the blade b is formedwith a relativelythin edge 12 which may be produced by roundin chamfering, or otherwiseshaping the rear face of the blade b at the inner end thereof, as shownat I3 in Fig. 3.

Toobtain a high degree of directional control of the thrown material andtoinsure a smooth movement of substantially all of the abradant materialonto the inner end of the blade during a predetermined limited arc ofrotation thereof, a tubular control member is provided. As shown moreparticularly in Figs. 2, 3 and 5, the tubular control member or controlsleeve 50 comprises a tubular side wall i5 which is generallycylindrical in exterior and interior outline. The inside surface of wall15 may be slightly spiralled in crosssectional contour, as indicated inFig. 3, thereby aiding the feeding of abradant and preventing choking.The inner end of the tubular side wall I5 may be entirely closed by anend wall It, shown more particularly in Figs. 2 and 5.

A discharge outlet is provided in the side wall L5. This outlet maycomprise a single opening adjacent the path of rotation of the innerends of the throwing blades b or may be constituted by a plurality ofsuitably disposed openings, such as shown in Patents Nos. 2,077,635 and2,077,636, which may be so dimensioned and arranged as to provide anabrasive stream of substantially uniform distribution of abrasive, orwhich may impart to the stream any other desired distributioncharacteristic.

The tubular control member extends into the central space a defined bythe inner ends of the blades b of the rotor with the closed end Itpositioned adjacent the rear rotor disc i. Preferably, the free edge I!of the tubular side wall l extends beyond the adjacent side flange H ofthe blades and, as shown in Fig. 2, may com-en iently extend beyond theoutside face of the side wall plate 2. The tubular control member doesnot rotate with the rotor but remains in a stantially fixed orcontrolled position during op eration.

The clearance between the inner ends of the blades b and the side walli5 of the tubular control member should be small, and preferably, onlysuchclearance is provided as is necessary to insure safe operation ofthe rapidly rotating rotor with respect to the stationary controlsleeve.

The control sleeve may be mounted in fixed normally stationary positionby any suitable means. Referring now to Figs. 2 and 5, such mountingmeans may comprise a hollow stud it which projects inwardly and 'issecured to the end wall it of the control sleeve, sufficient space beingprovided between the hollow stud l8 and the inside contour of thetubular side wall iii of the control sleeve to permit satisfactoryrotation and operation of impeller vanes (hereinafter described) ofsuitable size therebetween.

The abrasive is fed into the hollow stud l8 and escapes through one ormore discharge openings 09' therein, the openings it being defined bysuitable legs or straps l9 forming a part of the control sleevesupporting stud. The supporting stud l8 may be suitably secured to theend of and supported by a supply pipe 20 of such length and of suchdiameter as to supply the required amount of the abradant material to bethrown from the wheel.

A suitable supply hopper or funnel 2!, which may be secured to the upperend of the feed pipe 20, is so shaped as to assist the movement of thematerial into the feed pipe 20. In the event the tubular control sleeveis mounted on the end of the supply pipe 20, it is necessary that thesupply pipe 20 be securely mounted in fixed position, so that nomovement of the tubular control sleeve during operation of the wheelwill There is illustrated in Figs. 1 and 2 one form of supply. pipe andcontrol sleeve support which may be used. A foot plate 22, which mayintegrally be secured to the feed pipe 20 by a supporting web 23, isarranged to rest on a supporting bracket 30. The supporting bracket maybe provided with a flange 29 secured as by apair of spaced bolts 28 toan upwardly extending flange 21 on another bracket 20', having a footportion 25 which rests upon a fixed frame member or abutment 24 and issecured thereto as by a bolt or bolts 26.

The downwardly extending flange portion 29 of the supporting bracket tomay be provided with a slot 29' to receive the bolts 28 and whichpermits shifting of the feed pipe as and the control sleeve mountedthereon axially with respect to the central space a of the rotor.Likewise, the foot portion 22 associated with the feed pipe 20 may alsobe provided with a slot 32 through which the bolt 3!! extends to permitlateral shifting of the feed pipe 2% and the control sleeve mounted onthe end thereof to properly center the control sleeve within the centralspace a of the rotor. The flange portion 21! oi the second bracket 38'may also be provided with vertically extending slots through which thebolts 28 extend to permit vertical adjustment of the feed pipe 20 andthe control sleeve attached to the inner end thereof. Thus, threeadjustments are provided to permit proper positioning and centering ofthe control sleeve within the central space a of the rotor.

The supply pipe 20 and the control sleeve may beheld in fixed positionby proper adjustment and tightening of the bolts 28. and M. It isappreciated that numerous different types of adjustable supports may beprovided for supporting the feed pipe 20 and the control sleeveassociated therewith.

To lessen the weight imposed upon the supporting bracket 20, the supplyfunnel or hopper 2| may be independently supported by an arm 33'extending upwardly from the foot portion 25, which arm is secured to abracket 34 as by bolts 34, the bracket 24 being suitably attached to thesupply funnel or hopper 2i.

A leakproof seal between the inner end of the supply pipe 20 and thehollow supporting stud projections occur which might impede the normalsmooth flow of the abrading material.

To further insure the seal-tight'flt between these parts, ashoulder 31may be provided on the interior of the feed pipe 20 against which abutsthe free end 29 of the fitting 36. Similarly, a shoulder 28 is providedon the hollow stud it against which abuts the free end 40' of the feedpipe .20. The control sleeve may be locked to the inner end of the feedpipe 2|] by a spring collar or. clip it provided with inwardlyprojecting studs 44. The hollow boss 25 provided on the innerend of thefeed pipe-10 15 provided with corresponding openings or apertures llthrough which the studs 44 may extend.

Corresponding apertures or openings l2 may be provided with the fitting38 forming a part of the hollow stud l8 on the control sleeve. The studs44 are of sufilcient length to extend through the apertures ll, the bossand into the apertures 42 oi the fitting 36. v

To permit the desired orientation of the discharge outlet 0 1n thetubular control sleeve, a plurality of spaced apertures 42 may beprovided in the fitting 35 so as to permit any desired rotativeadjustment of the control sleeve with respect to the feed pipe 20. Thus,the discharge outlet 0 in the control sleeve may be arranged in anyclock dial position relatively to the axis of the rotor so,

as from the apertures in which they are seated,

rotating the control sleeve the desired amount so as to permit the studsM and the clip 35 to snap into the selected apertures 62111 the fitting3t of the hollow stud associated with the control sleeve. An impeller isprovided to forcibly project the abradant out through the dischargeoutlet 0 in the control sleeve and in substantially the same directionas the direction of rotation of the blades b and at a velocity onlyslightly less than the angular speed of rotation of the inner ends ofthe blades. As shown more particularly in Figs. 2, 3 and 5, the impeller60 comprises a pair of spaced rings or side wall plates 5i'and 52between which are arranged a series of spaced abrasive throwing vanes53. Preferably, there is a vane 53 for each of the abrasive throwingblades 1) which are arranged so that each vane is positioned slightly inadvance of the corresponding blade in the direction of rotation, asillustrated in Fig. 3. The vanes 53 are mounted for rotation within thecontrol sleeve in the space between the side wall i5 and the hollow studi8, whereby abrasive which is V forced through the openings I9 isdeposited in a path of the vanes 53 and thrown out through the dischargeopening 0 of the control sleeve.

The vanes 53 and connected side plates 5| and 52 are securely mountedfor rotation withthe throwing blades b. A sleeve portion 59 extends outthrough the opening 2' in the side plate 2 and is attached to orpreferably integral with a rim portion 58 having a mounting ring orflange 55.

The flange 55 is attached to the outer wall of the side plate 2 as bybolts or screws 51 extending through openings 56 in the flange 55. Theflange 55 may be set back slightly so that the rim' 5. is set out fromthe face of the side plate 2 and accommodates the open end of the sidewall l5 of the control sleeve.

The sleeve portion 59 of the impeller is spaced from the edge of theopening 2' in the side plate 2 to provide a space to accommodate theside wall I5 of the control member 50, this space, however, beingpreferably only sufllciently large to permit the proper clearance, thuspreventing the accumulation of abradant material therein. The sleeveportion 59 is provided with a shoulder 54 to accommodate thecorrespondingly shaped portion l5 of the control sleeve 50.

In order to permit the escape or spillage of any abradant which entersthe space a defined by the inner ends of the blades b and which is notdeposited in the path of the blades b, one or more spillage openings 61.are provided. In the present embodiment the spillage openings ii areformed in the rim portion 58 of theimpeller and take the form ofelongated slots. Thus, if any abradant collects in the space a and isnot deposited in'the path of the blades b, it will be ejected throughthe spillage openings 60. The movement oi. the vanes 53 and the blades bwill agitate any abradant material sufiiciently so that it will eitherbe picked up by the vanes 53 and thrown into the path of the blades b orwill be carried to the openings BI and expelled therethrough.

The construction of the control member 50 and particularly the provisionof the completely closed end wall I6, minimizes or completely preventsthe leaking of abradant from the space within the side wall I5 and thussubstantially all the abrasive is positively directed and is hurledthrough the opening and into the path of the blades b. Since the free,open end of the side wall I extends past the edges of the blades andthrough the side wall 2, the abrasive in the sleeve is positivelydirected out of the wheel and there is little possibility of leakage ofabrasive into the space between the control sleeve and the blades andside plates.

The wheel may be assembled in a manner which will be apparent to thoseskilled in the art from an inspection of the drawings and a reading ofthe foregoing description. However, it should be noted that, if desired,the control sleeve, feed supply pipe and the impeller 60 can be firstassembled together, and these members thereafter assembled with theremainder of the wheel. In an analogous manner, whenever repairs oradjustments are to be made, the feed pipe, control member and impellercan be removed from the wheel as a unit.

In the operation of the wheel, the shaft 6 is rotated thereby rotatingthe hub member I, side plates I and 2 and throwing blades b as a unit.

ply pipe 20 and through the fitting 36 and is delivered into theinterior of the hollow stud I0 from which it flows through one or moreof the openings l9 and into the path of movement of the vanes 53. Therotating vanes 53 carry the abradant material with them and throw it outthrough the opening 0 and into the path of the blades b. The material ispicked up by the blades b and carried to the periphery ofthe wheel whereit is hurled from the blades at the desired velocity. The other factorsbeing equal, the direction of flight of the abrasive as it leaves thewheel is determined by the clock dial position of the opening 0. whichposition can be adjusted by adjusting the position of the control member50 in the manner previously described.

Certain modifications can be made in the structure hereinbeforedescribed without departing fromthe spirit of the invention. Referringnow 1 particularly to Figs. 6, 7 and 8, there is shown an embodiment oftheinvention wherein an altemative construction of control member isemployed, the remaining portions of the wheel being similar in allrespects to the corresponding parts illustrated in Figs. 1 to 5.

' v The wheel comprises a plurality of throwing blades I10 carried bysaid plates IM and I02 and suitably mounted on shaft I06 for rotation.as above described. The impeller I60 is carried on the side plate I02and has throwing vanes I53 disposed in the space a defined by the innerends of the blades I10, as described hereinbefore.

The feed pipe I leads to the space a and communicates with and supportsa control member I50 of modified construction. The control member I50comprises a tubular side wall H5 having an opening 0 or a plurality ofopenings, as disclosed in the patents above referred to. The tubularside wall member 5 is closed at'its side opposite the feed end of thewheel by an end tube I20, a fitting I36 preferably of cylindrical formbeing provided for this purpose. The fitting I36 preferably is formedintegral with the stud M9 and is machined on its outer surface toprovide a sealtight fit with a hollow boss I formed on the end of thefeed tube I20. A shoulder I31 is provided on the feed pipe against whichthe free end I39 of the fitting I36 abuts. Similarly,

a shoulder I38 is provided on the stud I I0 against which the free endN0 of the feed pipe abuts.

A springcollar or clip H3 is provided having inwardly extending studsI54 which project through openings MI of the feed pipe I20 an enterrecesses I62 in the fitting I36.

Referring now toFigs. 11 and 12 there is shown an alternative form ofmeans'for securing the control member to the feed pipe. In thisembodiment of the invention the control member can be adjusted to anyone of an infinite number of positions angularly about the axis of thewheel. The control member 250 is formed in a manner generally similar tothe control member but, instead of being locked to the supply pipe by apositively positioned means, is secured frictionally, whereby very closeadjustments can be obtained.

In this construction the supply pipe 220 is provided with an enlargedend or boss 235 into which is telescoped a fitting or cylindricalexten-'- sion 236 of the control sleeve 250. The free end of the fitting236 abuts a shoulder 23'! on the supit can be slightly contracted tofrictionally grip the fitting 236. Lugs 2 80 are formed adjacent theends of the split boss 235 and are provided with registering openings28I through which a bolt 282 is extended and secured as by a nut 283.When the boss 235 is contracted slightly by tightening the nut and boltit tightly g ips the fitting 236. It will be understood that there is aclose machine-fit between the'fitting 226 and the boss 235 so that avery minute contraction of the boss I In the construction illustrated inFigs. sand 10,

the impeller comprises a plurality of vanes 353 carried between sidewall members 85! and 352. The vanes and side wall members are supported5 by a sleeve portion 359 which extends out through the opening 302' inthe side wall plate 302. The sleeve portion 359 is integral with andcarried by a mounting flange 355 extending substantially perpendicularlyto the sleeve portion 359. The

mounting flange 355 is of substantial thickness side wall 3 l 5 of thecontrol member 35% and which is not thrown into the path of movement ofthe throwing blades Bill, is discharged through the spillage ducts 36E.The movement of the vanes 353 and the blades 3W tends to agitate suchmaterial and assist its movement toward the ducts.

' After the material enters the ducts it is caused to flow therethroughby the centrifugal force created by the rotation of the impeller and isforcibly ejected from the outer ends of the ducts.

It will be understood that either form of control member, either form ofmeans for securing the control member to the supply pipe or either formof impeller may be employed with either of the forms of the remainingmembers of the wheel.

5 In other words, where alternative constructions are shown, eitheralternative'canbe employed in a wheel constructed in accordance with theinvention.

From the foregoing it will be seen that the 40 present inventionprovides an improved abrasive throwing machine wherein uncontrolledleakage or spillage of abrasive material from the control member intothe path of rotation of the blades is minimized or substantiallyprevented. The abrasive material is positively and efliciently deliveredto the vanes of the impeller and the possibility of undue wear orclogging of the wheel is reduced to a minimum. The construction providesa simple and eflicient manner of mounting the impeller by 60 which theimpeller can be securely and positively fixed relative to the throwingblades and prevented from turning or becoming displaced in such a way asto change the predetermined clearance between the rotating andstationary parts of the wheel. i

The present invention provides a structure in which the supply pipe,impeller and control member occupy a minimum of the space within theinner ends of the throwing blades and interfere to the minimum extentwith the smooth and full How of abrasive material from the hopper to thethrowing blades. Furthermore, the novel construction of supply pipe andcontrol member permits a smooth unimpeded flow of abrasive materialwithout any liability of clogging or choking.

While certain novel features of the invention have been disclosedherein, and are pointed out in the annexed claims, it will be understoodthat various omissions, substitutions and changes may 7 be made by thoseskilled in the art without de- 1 parting from the spirit of theinvention.

It is to be understood that the term abrasive,

ing action or capable of hardening or polishing the articles treated.Such material may consist of smooth particles, such as steel shot, orsharp abrasive particles, such as cracked steel grits or clean sharpquartz sand or other materials suit- 5 able for cleaning, hardening,polishing or otherwise modifying the surface characteristics of thearticles in the desiredmanner.

What is claimed is:

1. A machine for throwing abrasive comprising 10 a rotor includingspaced parallel side members having throwing blades between said sidemembers extending from the periphery of said rotor inwardly short of theaxis of rotation thereof to provide a central space, means for feedingabral5 sive throughone of said side members to said space, an impellercarried by a side member at the feed side of said rotor and having vanesin said central space, and a control member having a tubular portion insaid space between said vanes 20 and said. blades and formed with aninlet opening at the feed side of said rotor and a discharge openingadjacent the path of rotation of the inner ends of said blades.

2. A machine for throwing abrasive comprising 25 a rotor includingspaced, parallel, side members having throwing blades carried betweensaid side members and extending from the periphery of said rotorinwardly short of the axis of rotation thereof to provide a centralspace, an impeller supported from one of said side members and havingvanes in said central space, a spillage opening for abrasive leadingfrom said space through said impeller, a relatively stationary controlmember having a'tubular portion in said 35 space between said vanes andsaid blades, said tubular portion having a discharge opening thereinadjacent the path of rotation of said blades, and means for feedingabrasive to said' rotor through the side member on which said '40impeller is mounted.

3. A machine for throwing abrasive comprising in combination, a rotorincluding a plurality oi throwing blades extending from the, peripheryinwardly short of the axis of rotation of the rotor 45 to provide acentral space, a relatively stationary control member having a tubularportion disposed in said central space, an impeller having a plu-.rality of vanes rotatable with said throwing blades extending into saidtubular portion, a-discharge opening in the wall of said tubularportion, and means extending through said impeller for mountingsaidcontrol member in normall stationary position 1 4. A machineforthrowing abrasive comprising 55 in combination, a rotor including aplurality of rotatably mounted throwing blades extending from theperiphery inwardlyshort of the axis of rotation of said rotor to providea central space, means for feeding abrasive into said central space fromone side of said rotor, a control member rotatably mounted throwingblades extending 76 I from the periphery inwardly short of the axis 01'rotation oi said rotor to provide a centralspace, means for feedingabrasive into said central space from one side or said'rotor, animpeller having a plurality of vanes in said central space, means 1;

secured to said rotor at the feed side thereof for supporting saidimpeller for rotation with said blades, a relatively fixed controlmember having a tubular portion extending into said central spacebetween said vanes and said blades, and means extending through saidimpeller for supporting said tubular portion.

6. A machine for throwing abrasive comprising a rotor including aplurality of blades extending from the periphery inwardly short of theams of rotation of the rotor to provide a central space, an impellerrotatable with said blades extending into said space, a control memberhaving a tubular portion in said space between said impeller and saidblades and having a mounting portion extending within said impeller, afeed member for feeding abrasive to said impeller, and means ad-Justably supporting the mounting portion on said feed member.

7. A machine for throwing abrasive comprising a rotor including aplurality of'blades extending ijrom the periphery inwardly short of theams of rotation of the rotor to provide a central space, an

impeller rotatable with said blades extending into said space, a controlmember having a tubular control portion formed with a discharge opening,

said tubular control portion being disposed in said space between saidimpeller and said blades, and

a tubular feed portion within said impeller, and a tubular feed membercommunicating with said tubular feed portionand having substantialcontinuity of internal surface therewith, whereby abrasive material isdelivered through said feed member to the feed portion of said controlmember without spillage.

8. A machine for throwing abrasive comprising a rotor including aplurality of blades extending from the periphery inwardly short of theaxis of rotation of the rotor to provide a central space, an impellerrotatable with said blades extending into said space, a control memberhaving a tubular portion in said. space between said impeller and saidblades, and a tubular feed portion extending through said impeller, anda tubular feed member telescoping with said feed portion whereby saidfeed member and said feed portion provide a closed tube leading fromoutside said wheel to within said central space.

9. A machine for throwing abrasive comprising a rotor including aplurality of blades extending from the periphery inwardly short of theaxis of rotation of the rotor to provide a central space, an impellerrotatable with said blades extending into said space, a control memberhaving a tubular portion in said space between said impeller and saidblades, and a support for said control member extending through acentral opening in said impeller, a tubular feed spout, and means foradjustably mounting said support on said feed spout.

10. An abrasive projecting machine comprising a rotor'having a pluralityof rotatably mounted throwing blades extending from the peripheryinwardly short of the axis of rotation of the rotor to provide a centralspace, means for feeding abrasive into said central space from one sideof said rotor, an impeller fixed to rotate with said blades an abrasivespillage opening therein through which stray abrasive may escape.

11. An abrasive projecting machine comprising a rotor having a pluralityof rotatably mounted throwing blades extending from the peripheryinwardly short of the axis of rotation of the rotor to provide a centralspace, means for feeding abra- 3 sive to said rotor at one side thereof,an impeller fixed to rotate with said blades extending into said space,a control member having a tubular portion extending into said spacebetween said impeller and said blades, said control member having adischarge outlet in the tubular portion thereof for directing theabrasive into the path of rotation of said blades, said impellerincluding \a plurality of vanes rotatable in said tubular portion and amounting portion fixed to said vanes, extending over the edge of saidtubular portion adjacent the feed side of said rotor, and fixed to saidrotor.

JOHN E. GUENDLING,

